1. Field of the Invention
The present invention relates to polarized electromagnetic relays, and in particular to a polarized electromagnetic relay having a particularly compact arrangement of the yokes and armature.
2. Description of the Prior Art
A polarized electromagnetic relay having a magnet system consisting of two spaced angled yokes disposed parallel to one another with a permanent magnet disposed therebetween is described, for example, in German Pat. No. 966,845 corresponding to British Pat. No. 724,978. In this known magnet system, one leg of the yoke arrangement has an excitation coil wound thereabout and an armature mounted outside of the coil is disposed with at least one movable end between the parallel free ends of the two yokes comprising the yoke arrangement. The yokes are U-shaped and the armature is pivotally mounted so that when the coil is energized the armature is attracted to one of the yokes such that the opposite end of the armature moves in the opposite direction about the pivot point. Such a U-shaped yoke arrangement, however, cannot be subsequently introduced into a completed and wound coil body and in practice the coil body must be manufactured in two joinable parts which are assembled around the yoke arrangement and subsequently wound with magnet wire.
A U-shaped yoke arrangement is also known in the art having a central portion and a permanent magnet disposed between the yoke elements situated beneath the coil. Such a yoke arrangement is utilized with a bar-shaped armature which extends through the inside of the coil between the free ends of the yoke legs. Contact actuation is undertaken by means of a slide element disposed on the armature between the coil flange and the free yoke legs; the slide element actuating contact springs is disposed at opposite sides of the coil. This arrangement, however, does not make optimum use of the available space because the contact elements disposed at opposite sides of the coil are at the same level as the armature and thus require relatively long leads.